JP2012151568A - Image reading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading device capable of easily performing skew correction, when the deviation of a reading line is detected in a reading test.SOLUTION: A reading unit 19 includes an image sensor 31, a carriage 32 for supporting the image sensor 31 and an angle adjustment mechanism for adjusting the angle of the image sensor 31. By the displacement of the image sensor 31 to the carriage 32 using the angle adjustment mechanism, the angle of the image sensor 31 to a guide rail 20 is adjusted. The angle adjustment mechanism includes a first support body 33 and a second support body 34 provided on the carriage 32 for supporting the image sensor 31. The angle adjustment mechanism further includes: a guide structure 60 for guiding the second support body 34 in a displaceable manner around the first supporting body 33; and a fixed member 61 for fixing the second support body 34 to the carriage 32 at an arbitrary adjustment position.

Description

  The present invention relates to an image reading apparatus applied to a copying machine, a scanner, a facsimile, and the like. The present invention particularly relates to a skew correction structure for eliminating the inclination of a reading unit.

  Conventionally, in the field of image reading apparatuses, various methods for eliminating the inclination of the reading unit have been proposed. For example, in the image forming apparatus of Patent Document 1, a correction gap is formed in the rod through hole provided in the reading unit, and when stopped, the reading unit is inclined so as to obliquely intersect the sub-scanning direction. ing. Then, when the reading unit moves in the sub-scanning direction, the entire reading unit is shaken along the correction gap in the direction opposite to the moving direction, and the entire reading unit is displaced along the correction gap, thereby causing an image. The sensor reading line is made to coincide with the reference line.

  Also, to prevent the reading line from shifting during the assembly process of the image reading device, adjust the mounting angle of the guide rail to the document table using a jig, or use the jig to mount the reading unit to the guide rail. Therefore, it has been widely known to make adjustments (document unknown). As described above, if the position of the guide rail or the reading unit is adjusted in the assembling process, the deviation of the reading line when the assembling is completed can be eliminated to some extent.

JP 2008-32942 A

  In Patent Document 1, when moving in the sub-scanning direction, the reading unit of the image sensor is made to coincide with the reference line by intentionally displacing the entire reading unit along the correction gap. For this reason, it is necessary to form the rod through hole provided in the reading unit with high accuracy, which increases the cost. Furthermore, when a deviation occurs in the reading line in the reading test after assembling the image reading apparatus, the reading unit is separated from the guide rod, and after adjusting the dry bearing provided in the rod through hole, the reading unit is It is necessary to reassemble, and a lot of work is required for a series of adjustment work.

  In that respect, an image reading apparatus that uses a jig in the assembly process to adjust the mounting angle of the rail or adjusts the mounting posture of the reading unit can almost eliminate the deviation of the reading line when the assembly is completed. However, the reason why the reading line is shifted is caused by various factors other than the mounting angle of the rail or the mounting posture of the reading unit, and the deviation of the reading line cannot be completely eliminated, and some correction structure is necessary. It was.

  An object of the present invention is to provide an image reading apparatus capable of performing skew correction more easily when a deviation of a reading line is detected in a reading test. SUMMARY OF THE INVENTION An object of the present invention is to provide an image reading apparatus that can perform skew correction while a reading unit is placed on a guide rail, and thus can quickly perform skew correction with less effort.

  In the present invention, a reading unit 19 that reads a document, a guide rail 20 that supports the reading unit 19 so as to be movable along the sub-scanning direction, and a drive that moves the reading unit 19 along the guide rail 20. An image reading apparatus provided with the structure 21 is an object. The reading unit 19 includes an image sensor 31, a carriage 32 that supports the image sensor 31, and an angle adjustment mechanism that adjusts the angle of the image sensor 31. The angle of the image sensor 31 with respect to the guide rail 20 is adjusted by displacing the image sensor 31 with respect to the carriage 32 by an angle adjustment mechanism.

  As shown in FIG. 1, the angle adjustment mechanism includes a first support 33 and a second support 34 that are provided on the carriage 32 and support the image sensor 31. Further, the angle adjustment mechanism guides the second support 34 so as to be displaceable around the first support 33, and a fixing member 61 that fixes the second support 34 to the carriage 32 at an arbitrary adjustment position. including.

  The angle adjustment mechanism includes a first support 33 and a second support 34 that are provided on the carriage 32 and support the image sensor 31. Further, as shown in FIG. 9, the angle adjustment mechanism guides the first support 33 so as to be rotatable about the vertical axis and the second support 34 so as to be displaceable around the vertical axis 70. And a fixing member 61 that fixes the second support 34 to the carriage 32 at an arbitrary adjustment position.

  The first support 33 and the second support 34 support the image sensor 31 so as to be slidable up and down.

  The first support 33 is provided near one end of the image sensor 31 in the main scanning direction, and the second support 34 is provided near the other end of the image sensor 31 in the main scanning direction.

  The guide structure 60 and the operation portion of the fixing member 61 are arranged outside the outline of the image sensor 31 in plan view.

  In the present invention, the angle of the image sensor 31 with respect to the guide rail 20 is adjusted by displacing the image sensor 31 with respect to the carriage 32 by the angle adjusting mechanism. Therefore, in the present invention, skew correction can be easily performed when a deviation of the reading line of the image sensor 31 is detected in the reading test. Even after the image reading unit 5 is assembled, the deviation of the reading line can be easily corrected, so that the labor for skew correction can be reduced and the manufacturing cost of the image reading unit 5 can be reduced. Further, even when the reading unit 19 is placed on the guide rail 20, the reading line shift of the image sensor 31 can be corrected by a simple operation of simply displacing the image sensor 31.

  The angle adjustment mechanism includes a first support 33 and a second support 34 that support the image sensor 31, and a guide structure 60 that guides the second support 34 around the first support 33 so as to be displaceable. According to this, the angle of the image sensor 31 can be adjusted by a simple operation by simply rotating the image sensor 31 around the first support 33, and skew correction can be performed more easily.

  Alternatively, the angle adjustment mechanism includes a first support 33 and a second support 34 that support the image sensor 31, a vertical axis 70 that supports the first support 33 so as to be rotatable about a vertical axis, and a second support. And a guide structure 60 that guides the guide 34 to be displaceable about the longitudinal axis 70. According to this, the angle of the image sensor 31 can be adjusted by a simple operation by simply rotating the image sensor 31 about the vertical axis 70, and skew correction can be performed more easily.

  The first support 33 and the second support 34 support the image sensor 31 so as to be slidable up and down. According to this, since the image sensor 31 can be reliably brought into close contact with the platen glass 11 and the focal distance of the image sensor 31 can be kept constant, the image quality of the read image of the document can be stabilized.

  Since the first support 33 is provided near one end of the image sensor 31 in the main scanning direction and the second support 34 is provided near the other end of the image sensor 31 in the main scanning direction, fine adjustment of the angle of the image sensor 31 is simple. Can be done. This is because the sliding amount of the second support 34 accompanying the deviation correction can be increased when the deviation angle of the reading line is constant.

  Since the guide structure 60 and the operation portion of the fixing member 61 are disposed outside the outline of the image sensor 31 in plan view, the guide structure 60 and the operation portion of the fixing member 61 can be directly accessed from above, and thus the image sensor. 31 can be adjusted more easily.

1 is a cross-sectional plan view of an image reading apparatus according to the present invention. 1 is a conceptual diagram of a multifunction machine to which an image reading apparatus according to the present invention is applied. 1 is a plan view of an image reading apparatus according to the present invention. It is the BB sectional drawing of FIG. 6 which fractured | ruptured the center part. It is the BB sectional drawing of FIG. 6 which fractured | ruptured both ends. It is the sectional view on the AA line of FIG. It is a disassembled perspective view which shows a 2nd support body and its periphery structure. It is CC sectional view taken on the line of FIG. It is a figure equivalent to the AA line section of Drawing 1 concerning another embodiment.

(Embodiment) FIGS. 1 to 8 show an embodiment in which an image reading apparatus according to the present invention is applied to a multifunction machine having a copy function and a facsimile function. In the present invention, front / rear, left / right, and upper / lower follow the cross arrows shown in FIGS. 1 to 3 and the front / rear, left / right, and upper / lower indications shown near each arrow.

  In FIG. 2, the multi-function device 1 includes a paper feeding cassette 2, an image recording unit 3 that transfers a toner image to a recording paper conveyed from the paper feeding cassette 2, and a recording paper that has passed through the image recording unit 3. And a fixing unit 4 that fixes the toner image by performing a heating / pressurizing process. An image reading unit (image reading device) 5 is disposed above the image recording unit 3 and the fixing unit 4. An operation panel 6 having various operation buttons is provided on the front surface of the image reading unit 5. The image recording unit 3 includes a photoconductor unit 8 including a charging drum 7 and a toner cartridge 9 that supplies toner to the photoconductor unit 8.

  As shown in FIG. 3, the image reading unit 5 includes a document table 12 on which a platen glass 11 on which a document to be read is placed is disposed, and a document pressing cover 13 that presses the document against the platen glass 11 and closely contacts the platen glass 11. The document pressing cover 13 is supported by a pair of left and right hinges 14 and 14 provided at the rear end of the document table 12. As shown in FIG. 4, the document table 12 is formed in a box shape with a square box-shaped frame 16 that opens upward, a frame cover 17 that closes the upper opening of the frame 16, and the like. A square opening is formed at the center of the frame cover 17, and the platen glass 11 is assembled to the center opening.

  The frame 16 includes a reading unit 19 that reads a document, a guide rail 20 that supports the reading unit 19 so as to be movable in the left-right direction (sub-scanning direction), and the reading unit 19 along the guide rail 20. A drive structure 21 for movement is provided. As shown in FIG. 1, the guide rail 20 is disposed slightly in front of the center of the reading unit 19 in the front-rear direction (main scanning direction), and the rear end portion of the reading unit 19 is disposed in parallel with the guide rail 20. The support rail 22 is supported from below. As shown in FIGS. 4 and 5, the guide rail 20 and the support rail 22 are formed integrally with the frame 16. A trapezoidal guide surface that guides the reading unit 19 is formed on the upper surface of the guide rail 20.

  As shown in FIG. 1, the drive structure 21 includes a driving pulley 25 that is fixed to the output shaft of the motor 24 and rotates in a horizontal plane, a driven pulley 26 that is disposed corresponding to the driving pulley 25, and both pulleys 25 and 26. And a timing belt 27 wound around the belt. The driving pulley 25 is arranged at the right rear corner of the frame 16, and the driven pulley 26 is arranged behind the left end of the guide rail 20. A pair of direction changing pulleys 28 is disposed in front of the driving pulley 25. The timing belt 27 located between the driven pulley 26 and the direction changing pulley 28 is arranged in parallel with the guide rail 20, and the timing belt 27 located between the driving pulley 25 and the direction changing pulley 28 is arranged on the guide rail 20. Are arranged in the front-rear direction in a state orthogonal to A belt clamp 29 is provided on the lower surface of the carriage 32 described later. The belt clamp 29 is connected to the timing belt 27. As described above, the reading unit 19 can be moved in the left-right direction (sub-scanning direction) along the guide rail 20 along with the movement of the timing belt 27.

  As shown in FIG. 1, the reading unit 19 includes a contact-type image sensor (hereinafter simply referred to as CIS) 31 that reads a document, and a carriage 32 that supports the CIS 31. The CIS 31 is supported by a first support 33 and a second support 34 provided on the carriage 32 so as to be slidable up and down, and is urged by a compression coil spring 35 toward the platen glass 11. The springs 35 are arranged at two positions in the front and rear between the CIS 31 and the carriage 32.

  As shown in FIG. 6, the CIS 31 is configured by accommodating a pair of left and right xenon lamps 37, a lens array 38, and an image sensor substrate 39 in a rectangular box-like housing 36 that is long before and after opening upward. Yes. The upper opening of the housing 36 is closed with a transparent protective cover 40. The CIS 31 reads the original image by irradiating the light emitted from the xenon lamp 37 of the housing 36 toward the original and coupling the reflected light from the original onto the image sensor substrate 39 via the lens array 38. Spacers 41 are formed on the front and rear ends of the upper surface of the housing 36 so as to protrude. The spacer 41 is provided in close contact with the lower surface of the platen glass 11 so that the focal point of the CIS 31 coincides with the document surface.

  The carriage 32 is formed in a box shape long before and after opening upward, and the lower surface thereof is formed with the belt clamp 29 and the slide block 42 guided by the guide rail 20 protruding downward. (See FIG. 5). On the lower surface of the slide block 42, a slide surface 43 received by the guide rail 20 is formed in an inverted V shape.

  As shown in FIG. 1, support blocks 45 and 46 are provided on the front and rear of the right side wall of the housing 36, and first and second slide shafts 47 and 53 are respectively provided on the rear surfaces of these support blocks 45 and 46. Is provided in a state of protruding backward. The first and second slide shafts 47 and 53 are supported by the first support 33 and the second support 34 so as to be slidable in the vertical direction.

  As shown in FIG. 6, the first support 33 is a plate-like body that is formed integrally with the carriage 32 and extends in the vertical direction, and has a long slot in the vertical direction that supports the first slide shaft 47 at the center in the left and right direction. A first guide hole 48 is formed. As shown in FIGS. 7 and 8, the second support 34 is a molded product integrally including a support wall 49 extending in the vertical direction and an adjustment base 50 formed at the lower end of the support wall 49. In the center of the left and right sides of the support wall 49, a long second guide hole 54 that is long in the vertical direction and supports the second slide shaft 53 is formed. The adjustment base 50 is a plate body that is long in the left-right direction. A total of three screw holes 51 that allow screws to be inserted and a pair of left and right adjustment holes 52 and 52 that are provided so as to sandwich the screw holes 51. Each hole is formed in a vertically penetrating manner. The screw-through hole 51 and the adjustment holes 52 and 52 are long holes extending in the left-right direction in plan view, and the side edges in the length direction are centered on a vertical axis passing through the first guide hole 48 of the first support 33. Are curved in a partial arc shape (see FIG. 1).

  As shown in FIG. 1, a slide groove 55 is formed in the front and rear halfway portion of the rear support block 46 so as to penetrate vertically, and the positioning piece 56 provided on the inner surface of the carriage 32. I support it. The positioning piece 56 includes a support arm 57 extending from the inner surface of the carriage 32 and a round shaft-shaped restriction shaft 58 provided at the free end of the support arm 57, and the outer peripheral surface of the restriction shaft 58 is the inner surface of the slide groove 55. Is in contact with Thus, by supporting the vertical slide groove 55 with the positioning piece 56, the housing 36 can be positioned back and forth while allowing the housing 36 to slide up and down.

  In the present embodiment, the reading unit 19 includes an angle adjustment mechanism that adjusts the angle of the CIS 31 with respect to the guide rail 20. The angle adjusting mechanism includes a first support 33 and a second support 34 that are provided on the carriage 32 and support the CIS 31, and a guide structure 60 that guides the second support 34 around the first support 33 in an adjustable manner. And a screw body (fixing member) 61 or the like.

  Specifically, a slight margin is provided between the left and right walls of the first guide hole 48 of the first support 33 and the first slide shaft 47, and the CIS 31 and the second support 34 are connected to the first support. It can be displaced around 33. As shown in FIGS. 7 and 8, the guide structure 60 includes an adjustment base 50 of the second support 34, an adjustment hole 52 provided in the base 50, and a pair of guide pins 64 formed on the inner bottom of the carriage 32. Consists of. Thus, by guiding the adjustment hole 52 of the adjustment base 50 with the guide pin 64, the CIS 31 can be displaced around the first support 33 to adjust the position in the left-right direction. Further, the second support 34 can be fixed to the carriage 32 at an arbitrary adjustment position by screwing the screw body 61 inserted into the screw through hole 51 into the screw hole 65 of the carriage 32.

  The angle adjusting mechanism configured as described above can adjust the degree of horizontal inclination of the CIS 31 with respect to the carriage 32 by rotating the CIS 31 around the first support 33 and adjusting the position thereof. The angle of CIS 31 can be adjusted.

  When a deviation of the reading line of the CIS 31 is detected in a document reading test performed after the image reading unit 5 is assembled, the angle of the CIS 31 is adjusted by the following procedure. First, the platen glass 11 is removed from the frame 16 together with the frame cover 17, and the space above the carriage 32 and the CIS 31 is opened. Next, the screw body 61 is loosened, and the second support 34 is slid to the left or right around the first support 33 to correct the deviation of the reading line. After the adjustment, the screw body 61 is completely screwed into the screw hole 65 to fix the second support body 34 to the carriage 32. Thereafter, the reading test is performed again to confirm whether or not the reading line is shifted, and adjustment work is performed again as necessary.

  As described above, in the present embodiment, when the reading line shift of the CIS 31 is detected in the reading test, the CIS 31 is rotated and adjusted around the first support 33 with respect to the carriage 32 to thereby adjust the skew. Correction can be performed easily. Even after the image reading unit 5 is assembled, the deviation of the reading line can be easily corrected, so that the labor for skew correction can be reduced and the manufacturing cost of the image reading unit 5 can be reduced. Further, even when the reading unit 19 is arranged on the guide rail 20, the deviation of the reading line of the CIS 31 can be corrected by a simple operation by simply rotating the CIS 31.

  Since the first support 33 is provided at the front end of the CIS 31 and the second support 34 is provided at the rear end of the CIS 31, the angle of the CIS 31 is larger than when the second support 34 is disposed in the vicinity of the first support 33. Can be easily fine-tuned. This is because the sliding amount of the second support 34 accompanying the deviation correction can be increased when the deviation angle of the reading line is constant.

  The guide structure 60 and the operating head of the screw body 61 are arranged outside the outline of the CIS 31 in plan view, specifically, behind the CIS 31. According to this, since the guide structure 60 and the operating head of the screw body 61 can be directly accessed from above, the CIS 31 can be adjusted more easily.

  FIG. 9 shows another embodiment of the image reading apparatus according to the present invention. Here, the first support 33 is formed separately from the carriage 32, and the vertical axis 70 is formed at the lower end of the first support 33. The vertical axis 70 is rotatably supported by a shaft hole 71 provided in the inner bottom of the carriage 32, and is prevented from coming off by a retaining ring 72. The side edges in the length direction of the screw-through hole 51 and the adjustment holes 52 and 52 are curved in a partial arc shape with the central axis of the vertical axis 70 as the center. Unlike the above-described embodiment, no margin gap is formed between the left and right walls of the first guide hole 48 of the first support 33 and the first slide shaft 47.

  In this alternative embodiment, the CIS 31 is rotated around the vertical axis 70 to adjust the position, thereby adjusting the degree of horizontal inclination of the CIS 31 with respect to the carriage 32, thereby adjusting the angle of the CIS 31 with respect to the guide rail 20. Therefore, when a deviation of the reading line of the CIS 31 is detected in the reading test, the skew correction can be easily performed. Since others are the same as the above-mentioned embodiment, the same numerals are given to the same member and the explanation is omitted. In this case, the first support 33 is provided with the vertical axis 70 and the carriage 32 is provided with the shaft hole 71. On the contrary, a protruding vertical axis is provided on the inner bottom of the carriage 32 to provide the first support. A shaft hole can also be provided in the body 33.

  In addition, in each said embodiment, the screwing hole 51 of the 2nd support body 34 is not restricted to a long hole shape, For example, it can form in perfect circle shape or circular arc shape. Both supports 33 and 34 are not limited to the above arrangement, and for example, the front portion of the housing 36 can be supported by the second support 34 and the rear portion of the housing 36 can be supported by the first support 33. Further, one of the supports 33 and 34 may be disposed at the center in the front-rear direction of the CIS 31.

  As the fixing member 61, for example, a pin can be used in addition to the screw body. Specifically, one hole having the same diameter as the pin is formed in the second support 34, and a plurality of holes having the same diameter as the pin are formed in the carriage 32. The second support 34 is fixed to the carriage 32 by inserting a pin into the hole of the second support 34 and any hole of the carriage 32. When adjusting the angle of the CIS 31, the pin is once removed and the second support 34 is displaced, and after the adjustment, the pin is inserted into the hole again to fix the second support 34 to the carriage 32.

5 Image reading device (image reading unit)
12 Document table 19 Reading unit 20 Guide rail 21 Drive structure 31 Image sensor (CIS)
32 Carriage 33 First support 34 Second support 60 Guide structure 61 Fixing member (screw body)

Claims (6)

An image in which a reading unit that reads a document, a guide rail that supports the reading unit so as to be movable in the sub-scanning direction, and a drive structure that moves the reading unit along the guide rail are provided on the document table. A reading device,
The reading unit includes an image sensor, a carriage that supports the image sensor, and an angle adjustment mechanism that adjusts an angle of the image sensor,
An image reading apparatus that adjusts an angle of the image sensor with respect to the guide rail by displacing the image sensor with respect to the carriage by the angle adjusting mechanism. The angle adjusting mechanism is
A first support and a second support provided on the carriage to support the image sensor;
A guide structure for guiding the second support so as to be displaceable around the first support;
The image reading apparatus according to claim 1, further comprising: a fixing member that fixes the second support to the carriage at an arbitrary adjustment position. The angle adjusting mechanism is
A first support and a second support provided on the carriage to support the image sensor;
A longitudinal axis for rotatably supporting the first support around a vertical axis;
A guide structure for guiding the second support so as to be displaceable about the longitudinal axis;
The image reading apparatus according to claim 1, further comprising: a fixing member that fixes the second support to the carriage at an arbitrary adjustment position.   The image reading apparatus according to claim 2, wherein the first support and the second support support the image sensor so as to be slidable up and down. The first support is provided near one end of the image sensor in the main scanning direction;
The image reading apparatus according to claim 2, wherein the second support is provided near the other end of the image sensor in the main scanning direction.   The image reading apparatus according to claim 2, wherein the guide structure and the operation portion of the fixing member are disposed outside an outline of the image sensor in a plan view.

Images